The National Road Regulation states that it is illegal for passenger, 4×4, bakkies and taxi type vehicles to be fitted with regrooved tyres.

Regroovable tyres for trucks are specifically manufactured with an additional tread depth of up to 4mm.  This is called “tread stock” and is located between the upper edge of the belt and the tread grooves.  Tyres that may be legally regrooved are marked “Regroovable” on the sidewall areas, which means it has extra undertread thickness for regrooving purposes.

• The regrooving of tyres should be entrusted solely to a fully trained, manufacturer approved, operator.
• Only proven regrooving tools with electrically heated blades should be used.
• A minimum undertread rubber is required.  Regrooving is normally carried out when the original tread depth still has 3 to 6 mm remaining.
• Regrooving a truck tyre can provide up to 25% more kilometers.